<!DOCTYPE html>
<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        let data = {
            name: "尚硅谷",
            address: "北京",
            a: {
                b: 1
            }
        }

        //创建一个监视的实例对象,用于监视data中属性的变化
        const obs = new Observer(data);
        console.log(obs);

        //准备一个vm实例对象
        let vm = {}
        vm._data = data = obs

        function Observer(obj) {
            //汇总对象中所有的属性形成一个数组
            const keys = Object.keys(obj);
            //遍历
            keys.forEach((k) => {
                Object.defineProperty(this, k, {
                    get() {
                        return obj[k]
                    },
                    set(val) {
                        console.log(`${k}被改了,我要去解析模板了,生成虚拟DOM...我要开始忙了`);
                        obj[k] = val
                    }
                })
            })
        }
    </script>
</body>

</html>